The Basics: Some adolescent-minded men go to Las Vegas to get loose for a bachelor party weekend. They wake up without memory of the night before. One has lost a tooth, there's a stray baby and an angry tiger in their hotel room, one of them has a hospital bracelet and the groom is missing. Also, there's a chicken wandering around. They have to piece it all together, find the marrying man and get back to Los Angeles in time for the wedding.

What's The Deal: This movie's director, Todd Phillips, made a documentary called Hated in the 1990s about the late punk rock musician G.G. Allin, a guy who used to beat up audience members and slam himself in the mouth with his microphone, breaking his own teeth. And I kept thinking about G.G.A. every time Ed Helms's character with the bloody tooth socket would grin or make out with hooker character Heather Graham. In a way, you can draw a line from that documentary to this fictional comedy. It's a weird line, of course, since one film's subject died from his excess and the guys here get to swap blood-infused spit with prostitutes and everything turns out fine. But it's almost like, with Old School in between them, a thesis about the debauched fantasy life of American white guys. Look, I had to figure out some reason for this movie to exist, so just indulge me.

How It's Like Angels & Demons: They have to piece together clues to solve the mystery before the wedding or everything will be ruined and groom may even be killed. More like A&D, every single clue fits neatly into place (except for the chicken, which just runs around as a visual non-sequitur) and they figure it out like clockwork. Of course, nothing here is as crazily awesome as Ewan McGregor skydiving from an exploding helicopter, but the probably didn't have the budget for that kind of thing.

Best Reason To See It: It's mostly funny throughout, but it's bearded stand-up comic Zach Galifianakis who steals the movie. His creepy character tips the scales into repellent and reminds you that there may, in fact, be cause to question the fun-loving nature of these guys. Even when the film is dragging and airless, he comes into a scene and knocks it out of the park every time with a word, a gesture, a line delivery. I can't even describe what happens in the scenes he has with the mystery-baby in a non-profane way, but when that kid grows up he's going to be either really embarrassed or totally popular for having been in this film.

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